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Hard Water Options

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Steve_F

Mechanical
Dec 23, 2022
2
Hello Everyone

I'm a new member here and a facilities maintenance manager for a local municipality. Our Town Hall and Emergency Services buildings both have well water supply that is high in iron content and other minerals that raises havoc with heating equipment. My boiler make-up water regulator scales up and seizes after just 6 months in place. I've lost a 10 year old high efficiency boiler due to scaling. We have a water company that monitors our water daily as required by the Health Dept. for bacteria and operates a whole building chlorinating system for us but they don't address hardness.

My boilers and water heater are in the same room and I'm considering some kind of water treatment for the lines going to the boiler and water heater only. My thoughts are to run through a sediment filter first and then hardness correction, I'm open to suggestions. The more I learn about salt based softeners the less I like them so I'm trying to stay away from that route. I've been reading up on reverse osmosis but it's pretty confusing to me and I'm not even sure that it corrects hardness. There would not be a high demand on these isolated lines, boiler makeup is minimal as there are no apparent leaks, makeup seems to be due to evaporation. Our hot water consumption I would bet is less than 50 gallons a day, it's just restroom faucets supplied.

Would reverse osmosis be a viable option here? Any other suggestions besides a salt based softener?

Thanks so much!

 
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The biggest issues with RO are the pre-treatment and the high bypass flows. It is difficult with small intermittent systems.
What is the issue with Na based ion exchange units?
The other option is ion exchange using acid regen.
Though you could rent the bottles. it is usually 3, anion, cation, and a mixed bed polishing at the end.
If you get a good detailed water analysis (all ions) they can tailor the resin selections for you.
You watch conductivity and when it rises you change to fresh bottles.

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P.E. Metallurgy, consulting work welcomed
 
Part of my job is winter weather response and I've received training on the use of salt as a melting agent, and part of that training is the environmental impact of salt. Once an area is contaminated it doesn't go away. Both of these facilities have septic systems that leach into the ground and the salt used in the regeneration cycles will eventually end up in the ground. Seems like I'd be creating another problem trying to solve one.

Do these acids neutralize as they are consumed? I assume they would be going to our septic system as well? Thanks for the reply!
 
My softener dumps into my septic and the amount of salt used is so small that it wouldn't matter.
I use less than 20#/mo in regen for a household of 4.
The acid units either have their own acid regeneration unit or the acid is shipped to a site that can do it.
Look into renting ion exchange bottles.
That would be easiest.

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P.E. Metallurgy, consulting work welcomed
 
You may end up putting more salt into the septic system with the RO system than the water softener. The RO system will also have a reject stream that will route about 10-15% or the through put into the septic system.

You should have a water softener installed on just the boiler makeup water. If you have other facilities such as kitchens, install sink mounted RO systems. These other facilities may also use low pressure softeners that don't produce zero hardness water.
 
The starting point for the decision is that you need to get a comprehensive water analysis of the water that you are proposing to use. No matter who advises you and whoever is going to supply and install systems for you will require at least one but preferably a couple of comprehensive chemical analysis so that systems can be correctly sized. You will also need to know how much water each of these systems use, both in terms of how much daily, weekly and maybe even monthly but what is the peak flow. This will allow decisions to be made on equipment sizing and whether "treated" water tanks with lower capacity treatment systems might be better than supplying a large machine capable of dealing with short term peaks.
Your utility meter reads will be a great start even if you have no other data on the flow requirements.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"
 
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